Mexican and foreign tourists arrive at an Air Force hangar in Mexico City after being airlifted out of the hurricane-ravaged resort area of Los Cabos by the Mexican armed forces, in Mexico City, Tuesday, Sept. 16, 2014. Travelers are being flown free of charge to airports in Tijuana, Mazatlan, Guadalajara and Mexico City to catch connecting flights and, in the case of foreigners, receive consular assistance. (AP Photo/Christian Palma)

Mexican and foreign tourists arrive at an Air Force hangar in Mexico City after being airlifted out of the hurricane-ravaged resort area of Los Cabos by the Mexican armed forces, in Mexico City, Tuesday, Sept. 16, 2014. Travelers are being flown free of charge to airports in Tijuana, Mazatlan, Guadalajara and Mexico City to catch connecting flights and, in the case of foreigners, receive consular assistance. (AP Photo/Christian Palma)

A tourists disembarks from a military plane at an Air Force hangar in Mexico Ci…

The idea of Scottish independence has moved from the implausible to the very possible. Whether or not it actually happens, the idea that the union of England and Scotland, which has existed for more than 300 years, could be dissolved has enormous implications in its own right, and significant implications for Europe and even for global stability.

The United Kingdom was the center of gravity of the international system from the end of the Napoleonic Wars until World War II. It crafted an imperial structure that shaped not only the international system but also the internal political order of countries as diverse as the United States and India. The United Kingdom devised and drove the Industrial Revolution. In many ways, this union was a pivot of world history. To realize it might be dissolved is startling and reveals important things about the direction of the world.